The Telegraph’s Harry De Quetteville investigates the hidden stories behind three of Winston Churchill’s most iconic speeches, plus we speak to Oscar, Golden Globe and Writers Guild winner, Gary Oldman on playing Churchill.

The Nazis have turned West, invading France. In Britain Chamberlain has resigned. And in this, the first of four podcasts about Churchill's great wartime speeches, relatives and colleagues describe how Winston spoke to save his own political life on becoming PM in May 1940.

Churchill returns to the House of Commons on June 4 1940. His own position is more stable, but the country is on the brink. In this second podcast, Churchill prepares Britain for invasion, managing to inspire his audience, even as he hints at the worst.

In this third podcast, the fortunes of war have at last changed. It is November 1942, two years after Dunkirk, and the Allies have tasted victory for the first time. Churchill can savour - and even joke - about his new position of strength, while still warning of the sacrifices to come.

In this fourth podcast, actor Gary Oldman tells Telegraph film critic Robbie Collin how his own love of Churchill's speeches inspired him through the extraordinary process of playing the great man on film.